A power receiving capability of a device (hereinafter referred to as a “power receiving device”) that receives electric power is not constant in all power receiving devices and usually differs according to a power receiving device (for example, the type of power receiving device, a manufacturer, or a model). Further, as a power source that supplies electric power, there are various power sources such as a 100V power source and a 200V power source. For this reason, when electric power exceeding the power receiving capability of the power receiving device is supplied to the power receiving device, for example, an undesired situation in which the power receiving device is broken may occur.
In this regard, techniques of controlling transmission of electric power to a power receiving device have been developed. For example, a technique discussed in Patent Literature 1 has been proposed as a technique of invoking a state in which electric power can be transmitted to a power receiving device when a voltage of supplied electric power matches a previously set voltage.